In the preparation of certain foodstuffs where high standards of sanitation are necessary, it is customary to employ flow control valves constructed of stainless steel. Such valves have a high surface finish which is necessary to minimize the adherence of material and facilitate the frequent cleaning of disassembled valve parts.
When processing cheese curds, it is desirable to utilize a stainless steel valve in an automatic metal detect and divert system which normally allows forced air flow of cheese curd material from one processing station to another. Such a system is designed to automatically detect the presence of unwanted metal particles which sometimes appear in the process line from rust particles in water or from fragmented pieces of processing equipment. Upon detection of the contaminating metal, the system relies upon a divert valve for temporarily shifting the flow of material with the offending metal to a separate flow path, such as a refuse container. The divert valve must be responsive so as not to waste more material than is necessary.
It is known that there exists stainless steel ball valves which provide for three-way or diverted flow, such as disclosed in U.S. Pat. No. 2,905,197 issued Sep. 22, 1959 to Janes. In this type of valve, a generally spherical ball valve plug is rotatably mounted in a seating arrangement to control flow between two of the three passageways. Such a ball valve, however, is generally designed for liquid flow and is unsuitable for the processing of generally solid chunks of cheese curd. That is, the torsion control required for the ball valve would result in a poorly responsive valve which is liable to clog and cease to function. In addition, it is common knowledge that ball valves need to be completely disassembled when used in the handling of foodstuffs where cleaning is frequently required.
Given the nature of the lump-like cheese curds and the particular manner in which they are conveyed by forced air, it is desirable to provide a stainless steel divert valve which will efficiently act to instantaneously divert flow in accordance with a sensed condition that is, in this application, the presence of metal contaminant invading the process line. It is also desirable to provide a divert valve which may be cleaned in place without requiring disassembly of the valve. It is further desirable to provide a divert valve which may be adapted for controlling flow of liquid and liquid and solid mixtures of various viscosity, It is a general object of the present invention to teach a divert valve having a fast acting, linearly movable flow control member.
It is also an object of the present invention to teach a divert valve having no internal voids, crevices or screwthreads which will result in clogging.
It is a further object of the present invention to teach a divert valve which allows for cleaning in place (CIP) without requiring disassembly.
Yet a further object of the present invention is to teach a divert valve having a particularly configured flow control member conducive to improve flow diversion.
Still another object of the present invention is to teach a divert valve which enables efficient transfer of processed cheese curd.
It is also an object of the present invention to provide a stainless steel divert valve which avoids the use of a torsion controlled ball flow member.
Still yet another object of the present invention is the provision of a stainless steel divert valve which is responsive to a sensed condition and which is automatically actuated.
In one aspect of the present invention a divert valve includes a hollow body assembly having first and second ports axially aligned, and a third port extending generally perpendicularly to the first and second ports. A plug assembly is slidably mounted for linear movement within the valve body assembly. An actuator assembly is positioned exteriorly of the body assembly and is operably connected with the plug assembly such that in one position, the plug assembly allows communication between the first and second ports, and in a second position, the plug assembly allows communication between the first and third ports. The body assembly has a generally cylindrical inner wall, an open top and an open bottom for forming the third port. The body assembly further includes a pair of outwardly projecting ears, one of the ears defining the first port and the other of the ears defining the second port. The plug assembly includes a generally cylindrical disc slidably mounted relative to the inner wall of the body assembly for linear movement along the longitudinal axis, a pair of parallel, spaced apart stems extending upwardly from the disc and a baffling surface projecting downwardly from the disc. The baffling surface has a partial, cylindrically shaped rear surface and a downwardly sloping front surface. The downwardly sloping front surface includes a central triangularly shaped region provided with a pair of outwardly sweeping wings. The actuator assembly includes a cylinder housing having an inner wall, a cover attached to a top portion and a foot connected to a bottom portion by a first circular clamp. A piston is slidably mounted for linear movement along longitudinal axis in the cylinder housing, the piston being provided with a downwardly extending rod projecting through the foot. The rod has a free end connected to an actuating arm which is connected to the stems of the plug assembly.
The divert valve also includes a bonnet assembly extending between the body assembly and the actuator assembly. The bonnet assembly includes a circular base and a generally cylindrical tower projecting upwardly therefrom, the tower having open sides and a top ring which is lockingly engageable with the actuator assembly foot by means of a second circular clamp. The base is attached to the open top of the body assembly by a third circular clamp and is formed with a pair of diametrically opposed openings through which the plug assembly stems pass. A first sealing device is interposed between the base of the bonnet assembly and the open top of the body assembly. Second and third sealing devices are positioned between the piston and the inner wall of the cylindrical housing.
In another aspect of the invention, there is disclosed a three-way, flow valve having a body assembly including first and second axially aligned ports and a third port extending generally perpendicular to the first and second ports. The improvement resides in a flow control member slidably positioned for linear movement within the body assembly for selectively regulating flow through the first, second and third ports. The flow control member has a first structure for permitting normal flow between the first and second ports, and a second structure for diverting flow from the first port to the third port. The first structure is comprised of a generally cylindrical disc slidably mounted within the body assembly below the first and second ports during normal flow. The second structure is comprised of a baffling surface extending downwardly from the disc and terminating at a lower portion of the body assembly. With flow diverted, the disc is movable linearly above the first and second ports and the baffling surface is movable from the lower portion of the body assembly to a position between the first and second ports.
In yet another aspect of the invention, a flow control divert valve is provided for normally regulating material flow from a source to a first processing station, and diverting material from the source to a second processing station in response to a sensed condition downstream of the source. The divert valve includes a body assembly having an inlet port in communication with the source, a first outlet port in communication with the first processing station and a second outlet port in communication with the second processing station. A flow controlling plug assembly is slidably and non-rotatably mounted for movement along a longitudinal axis of the body assembly. The plug assembly includes a generally cylindrical disc over which material normally flows from the source to the first outlet port and first processing station. The plug assembly further includes a baffling surface depending from the disc, the baffling surface being constructed and arranged to selectively divert material flow from the source to the second outlet port and second processing station in response to the sensed condition downstream of the source. A fluid-actuated actuator assembly is associated with the body assembly and responsive to the sensed condition. The actuator assembly has a closed cylinder, a piston slidably mounted for linear movement in the cylinder, and a piston rod operably connected between the piston and the plug assembly disc. A first fluid intake is provided for selectively admitting fluid on one side of the piston, and a second fluid intake is provided for selectively admitting fluid on an opposite side of the piston. The admission of fluid causes the linear movement of the piston to be translated to linear movement of the plug assembly so as to selectively enable flow between the first processing station and the second processing station. At least the body assembly and the plug assembly are constructed of stainless steel.
The above and other objects and advantages of the present invention will become more apparent from the following description, claims and drawings.